05.07.2009
Balance of powers between boards of directors, senior management, shareholders and stakeholders of companies
A sales-weighted average fuel mileage calculation, in terms of miles per gallon, based on city and highway fuel economy measurements performed as part of the federal emissions test procedures
The act of deepening the wellbore in order to collect a cylindrical sample taken from a formation for geological analysis. A core bit is used to accomplish this (see core bit) together with a core barrel and a core catcher
Core drilling involves use of a core barrel, attached at the bottom of a string of rods, which is rotated and advanced through soil or rock to obtain a core sample of the material. Water or drill fluid is used to cool the cutting bit and to carry cuttings to the surface. There are two types of core drilling: conventional and wire line. To retrieve a core cut with a conventional core barrel, the entire string of drill rods must be removed from the hole. The wire line core barrel has an inner barrel which holds the core that can be pulled up through the drill rods thereby eliminating the need to remove the entire string of drill rods
A core bit is usually a drag bit often fitted with diamond cutting structures and has a hole in the middle which allows the bit to drill around a central cylinder of rock, which is taken in through the bit and into the core barrel